CLAWS

Part-of-speech (POS) tagging, also called grammatical tagging, is the commonest form of corpus annotation, and was the first form of annotation to be developed by UCREL at Lancaster. The POS tagging software for English text, CLAWS (the Constituent Likelihood Automatic Word-tagging System), has been continuously developed since the early 1980s. The latest version of the tagger, CLAWS4, was used to POS tag c.100 million words of the British National Corpus (BNC).